Compression refrigerating machine



y 3, 1938. w. HIRCHE 2,115,976

COMPRESSION REFRIGERATING MACHINE Filed March 21, 1936 I y-m2 Posted May 3,1938 I 2,115,976

COMPRESSION REFRIGERATING MACHINE Willy Hirche, Leopoldshain, Gorlitz-land, Germany, assignor to Berlin-Suhier Waffen-und Fahrzengwerke G. in. b. 11., Berlin, Germany Application March 21, 1936, Serial No. 70,168 In Germany March 22, 1935 2 Claims. (Cl. 62-115) This invention relates to a compression refrigmatically illustrated by way of example in the crating machine, in which a liquid refrigerant is only figure of the accompanying drawing. employed which does not combine with the 1ubri- In the form of construction shown by way of cant. The two liquids asfar as possible circulate example the compression refrigerating machine is separately. In the known refrigerating machines vertical.

of this type. trouble is frequently caused by one of An electric motor consisting of the rotor l and the liquids entering those parts of the apparatus of the stator 2 is located in a housing 3 mounted which should only receive the other liquid. The above acrank case 4 on the flanges of the latter. trouble is particularly serious when lubricating A vertical driving shaft 5, which carries the rotor oil escapes into the portions of the machine which I reciprocates a piston 8 in a compressor cylinder 10 are reserved for the refrigerant. This may be 9 by means of a crank 6 and connecting rod 1. A caused for instance by the machine being tilted condenser I3 is connected with the cylinder 9 and during transport or in the case of refrigerating an evaporator 12 is connected with the outlet end plants on trains or in ships by excessive vibration. of the condenser and the crank case 4. A con- 15 Moreover the refrigerant can enter in'the form of tainer Ill designedto hold a large quantity of 15 vapor the parts served with lubricant and then lubricating oil communicates with the bottom end condense therein. It is always difficult vto reof the crank case into a pump ll of any Suitable establish the correct working condition. construction mounted in the container Ill. The

It has been proposed to employ in a refrigeratpu p l is arranged at Such a height in h ing machine a larger quantity of lubricant than is tainer that it can only suck in lubricant. If the o necessary for the normal lubrication of the plant, r fri erant i h vi r an the l br n the p mp the object being to allow for the unknown quanwill be arranged higher in the container than if titles of oil which are withdrawn from the circulathe r fr rant s lighter than th lubricant. In

tion by collecting at different points of the maany case the qua tity of O in the Plant must be chine. t v greater than the combined capacities of the con- 25 A refrigerating machine has become known in denser l3 and evap 7 which the collecting chamber for the lubricant is e p a t Operates in e o ow mannerI- arranged in the crank case which is always under t W l he s ed t a condenser 3 and ev pvacuum. A second oil collecting chamber is also ra r I? v become mp y filled wi l provided in the evaporator from which lubricant n h Wh l of the r fr r n is in h c 30 must be returned to the crank casing. If in this tainer ll. The c ditions w ul then be the machine liquid refrigerant has entered the crank worst imaginable. There is then in the container case owing to displacement of the liquids, the ill above the liquid refrigerating medium t S refrigerant evaporates first and produces a certain much Oil that the p p l commences Operate over-pressure in the crank case which absolutely immediately the Plant is Started p and delivers 35 prevents lubricating oil being sucked into the l t th p ts to be lu a d. As n as th evaporator. A's less lubricant flows into the crank compressor 9 begins to Work, a vacuum is case than is consumed therein, the circulation of tabllshed in the container 50 that the liquid th lubricating n is t regulated. I refrigerant in the container Ill immediately com 40 This invention has for its object to avoid this memes to evaporate- The Vapors a Pressed into 40 inconvenience. This is attained by providing in the condenser and force the Fh the the compressor housing an especially large oil i e i theme the Eontamer The collecting'spacewhich is subjected to the suction hqmd refngemnt m the contamet. gradually of the compressor and making the combined evaporates and the whole of the oil is forced out capacities of the condenser and the evaporator of the condenser evaporator mto the container Ill. The plant commences to function small in relation to the quantity of oil and the properly after the first stroke of the piston and ac of the condenser Smaller than the the proper circulation of the liquids is re-estab- 0t liquidlreufrigerant. introduced- In a lished automatically without any external assistmachine which possesses these characteristics amcev 0 displacement liquids is Possible but quite If there is no liquid refrigerant in the container h l B even under the most adverse Circllm- Ill, but only lubricating oil, there must still be i h i t lubrication" nn fail a d the liquids sufficient oil to cover the suction end of the pump. fare-automatically returned to their proper places. The quantity of oil in the plant and also the An embodimentl of the invention is diagramposition'of the pump are determined by the two 55 extreme cases, namely that either the whole of the liquid refrigerant is in the container ill, or this container contains no liquid refrigerant.-

The pump must be arranged in such a manner that it is situated in the oil layer in both instances, that is, in thezone between maximum and minimum levels.

The liquids may also-become displaced by condensation during the time the plant is not working, if, for instance, a compressor is stored in an unprotected shed in the winter and is cooled by the air to a lower temperature than that prevailing in the evaporator in the refrigerating chamber. Also inthis instance the condensed product deposited in the crank case will be evaporated immediately the plant is started-up and any oil which may have become displaced will be immediately returned into the gear case.

It may happen that the condenser is completely filled with liquid refrigerating medium. If the condenser is capable of accommodating the whole quantity of liquid refrigerant the plant could not work as there would be no liquid refrigerant to evaporate. To make the plant absolutely reliable, it is further necessary that the capacity of the condenser is smaller than the quantity of liquid refrigerant introduced into the plant so that there is always a certain excess of liquid refrigerant in the evaporator or in the container l and evaporation can commence immediately the plant is started up. Instead of the pump other means may be provided to convey the oil to the points of lubrication, for instance lubricating chains, lubricating rings or contrifuging blades which dip into the oil and convey the same to the points of lubrication.

I claim:

1. A compression refrigerating machine comprising in combination a housing, a motor accommodated in said housing, a shaft driven by said motor and projecting from said housing, a crank formed on said shaft, a crank case accommodating said crank, a compressor driven by said crank and accommodated in said crank case, a condenser connected with said compressor, an evaporator forming an extension of said condenser, and connected to said crank case, a container forming an extension of said crank case, adapted to accommodate lubricant and refrigerant of different specific gravities, the combined capacities of said condenser and evaporator being less than the quantity of oil required to fill said container up to a point between the maximum and minimum levels of lubricant accommodated in said container.

2. A compression refrigerating machine as specified in claim 1 having a condenser of such size that its volumetric capacity is less than the quantity of. liquid refrigerant in the container mentioned in said claim 1.

WILLY HIRCHE. 

